﻿using System;
using System.Text.RegularExpressions;

namespace Calculator
{
    public class Calc
    {
        public int a, b, summ;
        public string input;

        public Calc(string _input)
        {
            input = _input;
        }



        public void Summ()
        {
            if (oper == "+")
            {
                summ = a + b;
                Console.WriteLine(summ);
            }
            else Console.WriteLine("error");
        }
            
    }

    class Program
    {
        static void Main()
        {
            string pettern = @"^(\b+)\s*([\+\-\*/])\s*(\b+))";
            string _input = Console.ReadLine();

            if (r && r1)
            {
                Calc calc1 = new Calc(a1, b1, oper1);
                calc1.Summ();
            }
            else Console.WriteLine("error");

            Console.ReadKey();
        }
    }
}
